Container precursor, in particular for the manufacture of a food container, from a laminate with a plastic gas and aroma barrier and a peeled edge region, which is partially folded back on itself

ABSTRACT

The invention relates to a container precursor comprising a wall, wherein the wall a) surrounds an interior region, and b) comprises a first wall region and a second wall region; wherein the first wall region comprises a first layer sequence comprising a first wall layer, a second wall layer and a third wall layer as overlying layers from the interior region outwards; wherein, in the first wall region, a second carrier layer is characterised by a smaller layer thickness than a first carrier layer, or a third carrier layer, or both; wherein the second wall region comprises a second layer sequence comprising first wall layer, a second wall layer and a third wall layer as overlying layers from the interior region outwards; wherein, in the second wall region, the second wall layer is connected to the third wall layer; wherein, in the second wall region, the third carrier layer is characterised by a larger layer thickness than the first carrier layer, or the third carrier layer, or both. Further, the invention relates to a process for manufacturing a container precursor, a container precursor obtainable through this process, a closed container, a process for manufacturing a closed container, a closed container obtainable through this process, a use of the aforementioned container precursor, and a further use of the aforementioned container precursor.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a U.S. national stage of, and claims thepriority benefit of, International Patent Application Serial No.PCT/EP2015/074770, filed Oct. 26, 2015 and also claims the prioritybenefit of German Patent Application Serial No. 10 2014 015 960.4, filedOct. 31, 2014, the text and drawings of which are hereby incorporated byreference in their entireties.

The present invention relates to a precursor of a container, inparticular for holding food, a process for manufacturing a containerprecursor, a container precursor obtainable by this process, a closedcontainer, a process for manufacturing a closed container, a closedcontainer obtainable by this process, a use of the abovementionedcontainer precursor and a further use of the abovementioned containerprecursor.

For a long time, both food for human consumption and pet food productshave been preserved in either a can or a glass jar closed with a lid. Insuch case, the storage life can be increased by sterilising the food andthe container, in this case the glass jar or the can, separately, as faras possible and then filling the container with the food and closing it.These measures for increasing the storage life of food, which have beentried and tested over a long period of time, have a number ofdisadvantages, however; for example subsequent re-sterilisation isnecessary. Because of their substantially cylindrical form, cans andglass jars have the disadvantage that very dense and space-savingstorage is impossible. In addition, the weight of cans and glass jarsthemselves is considerable, which leads to increased energy consumptionduring transport. Energy consumption for the manufacture of glass, tinplate and aluminium is also very high, even if the raw materials used inthe process come from recycling. In the case of glass jars, hightransport costs also aggravate the situation. Glass jars are usuallypre-manufactured in glass works and then have to be transported to thefood bottling plant, necessitating considerable transport volumes.Furthermore, glass jars and cans can only be opened with a great deal ofeffort or with the aid of tools, which is, therefore, inconvenient. Inthe case of cans, there is a high risk of injury caused by sharp edgesduring opening. With glass jars, it happens again and again thatsplinters of glass get into the food when the glass jars are beingfilled or the full glass jars are being opened which, in the worst case,can lead to internal injuries when the food is consumed. In addition,both glass jars and cans must have labels affixed to them to identifyand advertise the contents of the food. Information and advertisementscannot be printed directly on glass jars and cans. In addition to theactual printing, therefore, a substrate—a paper or a suitable film—aswell as a fixing medium—an adhesive or sealant—are necessary.

Other packaging systems for storing food for a long period of time withas few adverse effects as possible are known from prior art. These arecontainers manufactured from sheet-like composites—frequently alsoreferred to as laminates. Such sheet-like composites frequently consistof a thermoplastic plastic layer, a carrier layer consisting usually ofcardboard or paperboard, an adhesion promoting layer, a barrier layerand a further layer of plastic, as disclosed, inter alia, in WO 90/09926A2.

These laminate containers have many advantages over conventional glassjars and cans. Nevertheless, these packaging systems can still beimproved upon.

Laminate containers are frequently characterised in that they consist ofa laminate which has been folded several times, with opposite ends ofthe laminate being sealed one on top of the other to form, in the firstinstance, a shell- or tube-shaped precursor of a closed container. Theend areas sealed one on top of the other form a longitudinal seam, whichis also present in the closed container. Both on the inside and on theoutside of the container this longitudinal seam comprises a joint of thelaminate through which moisture can penetrate into the layer structureof the laminate, in particular the carrier layer consisting usually ofcardboard or paperboard. This must be prevented, at least on the insideof the longitudinal seam, because the container is designed to containfood containing water. In the prior art, a polymer sealing strip istherefore sealed on the inside along the length of the longitudinalseam. Such a sealing strip constitutes an additional component to beapplied in the manufacturing process of the container. The sealing stripis also a further component of an aluminium-free container which mustconsist of a sealable plastic with a barrier effect, such as an EVOHlayer. However, such a plastic, which is capable of forming a barrier,is relatively expensive, which is why the number of such components inthe container must be kept to a minimum. Also, the seal of the sealingstrip must be totally impermeable over the entire length of thelongitudinal seam so as to be able to prevent the ingress of moisture,as the seal and hence a seam along the entire length of the longitudinalseam on either side of the sealing strip faces the inside and hence thefood.

In general, an object of the present invention is to overcome, at leastpartially, a disadvantage resulting from the prior art. A further objectof the invention is to provide a container, or a container precursor, orboth, wherein a process for manufacturing the container, or thecontainer precursor, is selected from a group consisting of a processthat needs less time, or is cheaper, or requires fewer components, or acombination of at least two thereof. A further object of the inventionis to provide a container that is more stable against compression. Afurther object of the invention is to provide a container that can bemanufactured with a lower reject rate. A further object of the inventionis to provide a container, or a container precursor, or both, whereinthe container, or the container precursor, contains no additionalbarrier strips to seal the container, or the container precursor, on theinside. A further object of the invention is to provide a container, ora container precursor, or both, wherein as few seams or sealingconnections as possible are exposed to the food placed inside thecontainer, or the container precursor. A further object of the inventionis to provide a container, or a container precursor, or both, wherein aprocess for manufacturing the container, or the container precursor, ischaracterised by one selected from a group consisting of a processinvolving less dust formation, or less noise generation, or longerservice life of the cutting tool, or a combination of at least twothereof. A further object of the invention is to provide a container, ora container precursor, or both, wherein there is as little additionalbonding material, for example a sealing layer or an adhesive, aspossible between superimposed peeled areas of a carrier material of thecontainer, or the container precursor. A further object of the inventionis to provide a container, or a container precursor, or both, whereinthere is a greater choice of layer thickness of a peeled carrier layerof the container, or the container precursor. A further object of theinvention is to provide a container, or a container precursor, or both,wherein a peeled area of a wall of the container, or the containerprecursor, is more stable or more sturdy and, therefore, more durable oreasier to work, or both. A further object of the invention is to providea container, or a container precursor, or both, wherein a seam,preferably a longitudinal seam, of the container, or of the containerprecursor, is protected against the ingress of moisture on the inside,or on the outside, or both. A further object of the invention is toprovide a container, wherein the container's bacterial count is lowerfor the same amount of sterilisation. A further object of the inventionis to provide a container, wherein the container possesses a combinationof 2 or more of the abovementioned advantages. A further object of theinvention is to provide a process for the manufacture of containers,wherein the percentage of defective containers, or container precursors,produced by the process is lower. A further object of the invention isto provide a process for the manufacture of containers, wherein fewercontainers with an increased bacterial count are produced using theprocess. A further object of the invention is to provide a process forthe manufacture of containers, wherein a lower percentage of defectivecontainers can be produced using the process. A further object of theinvention is to provide a process for the manufacture of containers,wherein a lower production tolerance in connection with a seam,preferably a low variation in seam width, of the container can beachieved using the process. A further object of the invention is toprovide a process for the manufacture of containers, wherein the processexhibits increased process stability. A further object of the inventionis to provide a process for the manufacture of containers, wherein theprocess is simpler, or faster, or both. A further object of theinvention is to provide a process for the manufacture of containers,wherein less space is required to accommodate production plants for theimplementation of the process. A further object of the invention is toprovide a process for the manufacture of containers, wherein the processpossesses a combination of 2 or more of the above advantages.

A contribution to the at least partial fulfilment of at least one of theabove tasks is made by the independent claims. The dependent claimsprovide preferred embodiments which contribute to the at least partialfulfilment of at least one of the above tasks.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by embodiment 1 of a container precursor 1, comprisinga wall, wherein the wall

-   -   a) surrounds an interior region, and    -   b) comprises a first wall region and a second wall region;        wherein the first wall region comprises a first layer sequence        comprising a first wall layer, a second wall layer and a third        wall layer as overlying layers from the interior region        outwards; wherein, in the first wall region, the first wall        layer is connected to the second wall layer and the second wall        layer is connected to the third wall layer; wherein the first        wall layer, as first wall layer sequence from the interior        region outwards, comprises a first barrier layer comprising a        barrier plastic for 70% by weight or more, preferably for 75% by        weight or more, more preferably for 80% by weight or more, more        preferably for 85% by weight or more, more preferably for 90% by        weight or more, most preferably for 95% by weight or more,        relative to the weight of the first barrier layer, and a first        carrier layer; wherein the second wall layer, as second wall        layer sequence from the interior region outwards, comprises a        second carrier layer and a second barrier layer comprising the        barrier plastic for 70% by weight or more, preferably for 75% by        weight or more, more preferably for 80% by weight or more, more        preferably for 85% by weight or more, more preferably for 90% by        weight or more, most preferably for 95% by weight or more,        relative to the weight of the second barrier layer; wherein the        third wall layer, as third wall layer sequence from the interior        region outwards, comprises a third barrier layer comprising the        barrier plastic for 70% by weight or more, preferably for 75% by        weight or more, more preferably for 80% by weight or more, more        preferably for 85% by weight or more, more preferably for 90% by        weight or more, most preferably for 95% by weight or more,        relative to the weight of the third barrier layer, and a third        carrier layer; wherein, in the first wall region, the second        carrier layer is characterised by a smaller layer thickness than        the first carrier layer, or the third carrier layer, or both;        wherein the second wall region comprises a second layer sequence        comprising the first wall layer, the second wall layer and the        third wall layer as overlying layers from the interior region        outwards; wherein, in the second wall region, the second wall        layer is connected to the third wall layer; wherein, in the        second wall region, the third carrier layer is characterised by        a larger layer thickness than the second carrier layer, or the        first carrier layer, or both.

An embodiment of the invention 2 of the container precursor 1 isconfigured according to embodiment 1, wherein the first wall regionabuts the second wall region.

An embodiment of the invention 3 of the container precursor 1 isconfigured according to embodiment 1 or 2, wherein the first wall regionis characterised by a first width along the circumference of thecontainer precursor, wherein the first width is between 1 and 6 mm,preferably between 1 and 5 mm, more preferably between 2 and 4 mm, mostpreferably between 2 and 3 mm. The first layer sequence preferably hasthe first width along the circumference of the container precursor.

An embodiment of the invention 4 of the container precursor 1 isconfigured according to any one of the preceding embodiments, whereinthe second wall region is characterised by a second width along thecircumference of the container precursor, wherein the second width isbetween 1 and 10 mm, more preferably between 1 and 8 mm, preferablybetween 2 and 8 mm, more preferably between 2 and 6 mm, most preferablybetween 3 and 5 mm. The second layer sequence preferably has the secondwidth along the circumference of the container precursor.

An embodiment of the invention 5 of the container precursor 1 isconfigured according to any one of the preceding embodiments, wherein,in the first wall region, the layer thickness of the second carrierlayer is between 0.05 and 0.9 times, preferably between 0.1 and 0.85times, more preferably between 0.2 and 0.85 times, more preferablybetween 0.3 and 0.85 times, more preferably between 0.4 and 0.85 times,still more preferably between 0.5 and 0.8 times, most preferably between0.6 and 0.75 times the layer thickness of the first carrier layer, or ofthe third carrier layer, or of both layers.

An embodiment of the invention 6 of the container precursor 1 isconfigured according to any one of the preceding embodiments, wherein,in the second wall region, the layer thickness of the third carrierlayer is between 1.1 and 20 times, preferably between 1.1 and 15 times,more preferably between 1.1 and 10 times, more preferably between 1.1and 5 times, more preferably between 1.1 and 3 times, more preferablybetween 1.1 and 2 times, more preferably between 1.2 and 1.9 times,still more preferably between 1.2 and 1.8 times, most preferably between1.3 and 1.7 times the layer thickness of the first carrier layer, or ofthe second carrier layer, or of both layers.

An embodiment of the invention 7 of the container precursor 1 isconfigured according to any one of the preceding embodiments, wherein,in the second wall region, the first wall layer is not connected to thesecond wall layer. The first wall layer is preferably in contact with,but not connected to, the second wall layer in the second wall region.In the second wall region, preferably at least 20%, more preferably atleast 30%, more preferably at least 40%, more preferably at least 50%,more preferably at least 60%, more preferably at least 70%, still morepreferably at least 80%, still more preferably at least 90%, mostpreferably at least 95%, of a surface of the first wall layer facing thesecond wall layer is in contact with, and preferably not connected to,the second wall layer. Also, the first wall layer and the second walllayer are preferably held together in such a way that they are joinedtogether in at least one wall region, preferably the first wall region,abutting the second wall region. In the second wall region, the firstwall layer may be neither connected to nor in contact with the secondwall layer in a further embodiment. In a further embodiment of theinvention, the first wall layer and the second wall layer are connectedtogether in the second wall region preferably on at least 20%, morepreferably on at least 30%, more preferably on at least 40%, morepreferably on at least 50%, more preferably on at least 60%, morepreferably on at least 70%, still more preferably on at least 80%, stillmore preferably on at least 90%, most preferably on at least 95%, of asurface of the first wall layer facing the second wall layer. The firstwall layer and the second wall layer in the second wall region arepreferably pressed together, or sealed together, or both.

An embodiment of the invention 8 of the container precursor 1 isconfigured according to any one of the preceding embodiments, wherein,in the second wall region

-   -   a) a surface of the first carrier layer facing the second        carrier layer, and    -   b) a surface of the second carrier layer facing the first        carrier layer each does not comprise a cover layer, preferably        not a “coating” and is not connected to a cover layer,        preferably not a “coating”.

An embodiment of the invention 9 of the container precursor 1 isconfigured according to any one of the preceding embodiments, wherein,in the first wall region, a surface of the second carrier layer facingthe first carrier layer does not comprise a cover layer, preferably nota “coating” and is not connected to a cover layer, preferably not a“coating”.

An embodiment of the invention 10 of the container precursor 1 isconfigured according to any one of the preceding embodiments, whereinone selected from the group consisting of the first carrier layer, thesecond carrier layer and the third carrier layer, or a combination of atleast two thereof, preferably each carrier layer, comprises one selectedfrom a group consisting of cardboard, paperboard and paper, or acombination of at least two thereof.

An embodiment of the invention 11 of the container precursor 1 isconfigured according to any one of the preceding embodiments, whereinthe wall comprises a third wall region; wherein the third wall regioncomprises a third wall sequence comprising the first wall layer and thethird wall layer as overlying layers from the interior region outwards;wherein, in the third wall region, the first wall layer is connected tothe third wall layer; wherein the third wall are abuts against the firstwall region.

An embodiment of the invention 12 of the container precursor 1 isconfigured according to embodiment 11, wherein the third wall region ischaracterised by a third width along the circumference of the containerprecursor, wherein the third width is between 1 and 12 mm, preferablybetween 1 and 10 mm, more preferably between 1 and 8 mm, more preferablybetween 2 and 6 mm, more preferably between 3 and 6 mm, most preferablybetween 5 and 6 mm. The third layer sequence preferably has the thirdwidth along the circumference of the container precursor.

An embodiment of the invention 13 of the container precursor 1 isconfigured according to any one of the preceding embodiments, whereinthe barrier plastic has a weight average molecular weight in a rangefrom 3·10³ to 1·10⁷ g/mol, preferably from 5·10³ to 1·10⁶ g/mol, morepreferably from 6·10³ to 1·10⁵ g/mol.

An embodiment of the invention 14 of the container precursor 1 isconfigured according to any one of the preceding embodiments, whereinthe barrier plastic is selected from the group consisting of apolyamide, an ethylene vinyl alcohol copolymer and a polyvinyl alcohol,or a combination of at least two thereof. A preferred polyvinyl alcoholis a polyethylene vinyl alcohol.

An embodiment of the invention 15 of the container precursor 1 isconfigured according to embodiment 14, wherein the polyvinyl alcohol ischaracterised by at least one of the following properties:

-   -   a) an ethylene content in a range from 20 to 60 mol %,        preferably from 25 to 55 mol %, more preferably between 25 and        45 mol %;    -   b) a density in a range from 1.0 and 1.4 g/cm³, preferably from        1.1 to 1.3 g/cm³;    -   c) a melting point of more than 155 to 235° C., preferably of        more than 160 to 230° C., more preferably of more than 165 to        225° C.;    -   d) an MFR value in a range from 1 to 25 g/10 min, preferably        from 1.5 to 23 g/10 min, more preferably from 2 to 20 g/10 min;    -   e) an oxygen permeation rate in a range from 0.05 to 3.2 cm³·20        μm/m²·day·atm, preferably fro, 0.05 to 2 cm³·20 μm/m²·day·atm,        more preferably from 0.1 to 1 cm³·20 μm/m²·day·atm.

A preferred polyvinyl alcohol is a polyethylene vinyl alcohol.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a process 1, comprising thefollowing process steps

-   -   a) Provision of a sheet-like composite, comprising        -   i) A composite layer sequence, comprising            -   A) a composite carrier layer, and            -   B) a composite barrier layer, comprising a barrier                plastic for 70% by weight or more, preferably for 75% by                weight or more, more preferably for 80% by weight or                more, more preferably for 85% by weight or more, more                preferably for 90% by weight or more, most preferably                for 95% by weight or more, relative to the weight of the                composite barrier layer,        -   ii) an edge region, and        -   iii) an inner region adjoining the edge region;    -   b) Reduction of the layer thickness of the composite carrier        layer in the edge region;    -   c) Creation of a fold in the edge region to obtain a first edge        fold region and a further edge fold region, wherein the first        edge fold region and the further edge fold region abut against        each other along the fold;    -   d) Bringing the first edge fold region into contact with a first        part of the further edge fold region, and connecting a further        part of the further edge fold region to the inner region;    -   e) Creation of a further fold in the inner region to obtain a        first composite fold region and a further composite fold region,        wherein the further composite fold region comprises the edge        region; and    -   f) Connecting the first composite fold region to the first part        of the further edge fold region and the further part of the        further edge fold region.

An embodiment of the invention 2 of the process 1 is configuredaccording to embodiment 1, wherein, in process step e), the furthercomposite fold region comprises a part of the inner region; wherein, inprocess step f), the first composite fold region is further connected tothe part of the inner region.

An embodiment of the invention 3 of the process 1 is configuredaccording to embodiment 1 or 2, wherein, in process step b), reductionis carried out by peeling the composite carrier layer.

An embodiment of the invention 4 of the process 1 is configuredaccording to embodiment 3, wherein peeling is carried out by a rotatingtool.

An embodiment of the invention 5 of the process 1 is configuredaccording to embodiments 1 to 4, wherein, in process step a), thesheet-like composite comprises a crease, wherein, in process step e),the creation of the further fold comprises a fold along the crease.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a container precursor 2, whereinthe container precursor is obtainable through the process 1 according toone of its embodiments 1 to 5.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a closed container 1, obtainableby folding the container precursor 1 according to any one of itsembodiments 1 to 15 or the container precursor 2 according to itsembodiment 1 and closing the folded container precursor with a closingtool.

An embodiment of the invention 2 of the closed container 1 is configuredaccording to embodiment 1, wherein the wall surrounds the interiorregion on all sides, wherein the wall consists of a one-piece sheet-likecomposite. The closed container preferably does not comprise a floorthat is not formed in one piece with the sheet-like composite or a coverthat is not formed in one piece with the sheet-like composite, or both.

An embodiment of the invention 3 of the closed container 1 is configuredaccording to embodiment 1 or 2, wherein one selected from a groupcomprising the first layer sequence, the second layer sequence and thethird layer sequence, or a combination of at least two thereof,preferably each layer sequence, comprises a further carrier layer.

An embodiment of the invention 4 of the closed container 1 is configuredaccording to embodiments 1 to 3, wherein, in the first wall region andthe second wall region, the first wall layer is overlaid by a fourthwall layer on a side facing the interior region; wherein the fourth walllayer, as a fourth wall layer sequence from the interior regionoutwards, comprises a fourth carrier layer and a fourth barrier layer,comprising the barrier plastic for 70% by weight or more, preferably for75% by weight or more, more preferably for 80% by weight or more, morepreferably for 85% by weight or more, more preferably for 90% by weightor more, most preferably for 95% by weight or more, relative to theweight of the fourth barrier layer; wherein, in the first wall region,the second carrier layer is characterised by a smaller layer thicknessthan the fourth carrier layer; wherein, in the second wall region, thefourth carrier layer is characterised by a larger layer thickness thanthe second carrier layer, or the first carrier layer, or both. In thisembodiment, the first wall region and the further wall region preferablybelong to a head portion or to a bottom portion of the closed container.The fourth wall layer is preferably connected to the first wall layer inthe first wall region and the second wall region.

An embodiment of the invention 5 of the closed container 1 is configuredaccording to embodiment 4, wherein, in the third wall region, the fourthwall layer overlays the first wall layer on a side facing the interiorregion. The fourth wall layer is preferably connected to the first walllayer in the third wall region.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a process 2, comprising thefollowing process steps

-   -   a) Provision of the container precursor 1 according to any one        of its embodiments 1 to 15 or the container precursor 2        according to its embodiment 1;    -   b) Folding the container precursor; and    -   c) Closing the container precursor with a closing tool to obtain        a closed container.

An embodiment of the invention 2 of the process 2 is configuredaccording to embodiment 1, wherein food is introduced into the containerprecursor before process step c), preferably after process step b).

An embodiment of the invention 3 of the process 2 is configuredaccording to embodiment 1 or 2, wherein the closed container isautoclaved after process step c).

An embodiment of the invention 4 of the process 2 is configuredaccording to embodiments 1 to 3, wherein the container precursor issterilised before process step c), preferably after process step b), andpreferably before food is introduced into the container precursor.Sterilisation is preferably carried out through contact with gaseoushydrogen peroxide, or liquid hydrogen peroxide, or both. Contact ispreferably made through immersion, rinsing, or spraying, or acombination or at least two thereof.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a close container 2, obtainablethrough the process 2 according to any one of its embodiments 1 to 4.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a use 1 of the containerprecursor 1 according to any one of its embodiments 1 to 15 or of thecontainer precursor 2 according to its embodiment 1 for the manufactureof a closed container.

A contribution to the fulfilment of at least one of the tasks of theinvention is made by an embodiment 1 of a use 2 of the containerprecursor 1 according to any one of its embodiments 1 to 15 or of thecontainer precursor 2 according to its embodiment 1 for filling it withfood.

Preferred embodiments of components of a category according to theinvention, in particular of the container precursor, the processaccording to the invention and the closed container, are also preferredfor components of the same name, or corresponding components, of theother categories according to the invention.

Layers

Two layers are bonded to each other when their adhesion to each othergoes beyond van der Waals attraction forces. Layers that are bondedtogether are preferably sealed together, or glued together, or pressedtogether, or bonded through a combination of two or more of thesemeasures. Unless otherwise specified, in a layer sequence the layers mayfollow each other indirectly, that is to say with one or at least twointermediate layers, or directly, that is to say without an intermediatelayer. This is the case, in particular, with formulation, in which alayer overlays another layer. A formulation in which a layer sequencecomprises enumerated layers means that at least the specified layers arein the specified sequence. This formulation does not necessarily meanthat these layers have to be in immediate succession. A formulation inwhich two layers abut against each other means that these two layers arein immediate succession without an intermediate layer. However, thisformulation does not indicate whether the two layers are bonded togetheror not. Rather, these two layers may be in contact with each other.

Bonding

-   -   Bonding is preferably selected from the group consisting of        sealing, gluing and pressing, or a combination of at least two        thereof. In the case of sealing, the bond is created by means of        a liquid and its solidification. In the case of gluing, chemical        bonds form between the interfaces or surfaces of the two objects        to be bonded together, which create the bond. In the case of        sealing or gluing, it is frequently advantageous to press        together the surfaces to be sealed or glued. A preferred form of        pressing two layers is to press together a first surface of a        first of the two layers onto a second layer facing the first        layer of the second of the two layers over at least 20%,        preferably at least 30%, more preferably at least 40%, more        preferably at least 50%, more preferably at least 60%, more        preferably at least 70%, still more preferably at least 80%,        still more preferably at least 90%, most preferably at least        95%, of the first surface. A particularly preferred form of        pressing is sealing. Sealing preferably comprises the process        steps of heating, laying one on top of the other, and pressing,        wherein the process steps preferably follow each other in this        sequence. Another sequence is also conceivable, in particular        the sequence of laying the layers one on top of the other,        heating, and pressing. Preferential heating is heating of a        polymer layer, preferably a thermoplastic layer, more preferably        a polyethylene layer, or a polypropylene layer, or both. A        further preferred form of heating is heating of a polyethylene        layer to a temperature of between 80 and 140° C., more        preferably between 90 and 130° C., most preferably between 100        and 120° C. A further preferred form of heating is heating of a        polypropylene layer to a temperature of between 120 and 200° C.,        more preferably between 130 and 180° C., most preferably between        140 and 170° C. A further preferred form of heating is carried        out to a seal temperature of the polymer layer. A preferred form        of heating may be carried out through radiation, through hot        gas, through solids heat contact, through mechanical vibrations,        or through a combination of at least two of these measures. A        particularly preferred form of heating is carried out through        the excitation of an ultrasonic vibration.        Contacting

A preferred from of contacting is pressing together.

Cover Layer

A preferred cover layer is a “coating”. In paper manufacturing, a“coating” is a cover layer which comprises inorganic solid particles,preferably pigments and additives. The “coating” is preferably appliedas a liquid phase, preferably as a suspension or a dispersion, to asurface of a layer containing paper or cardboard. A preferred dispersionis an aqueous dispersion. A preferred suspension is an aqueoussuspension. A further preferred liquid phase comprises inorganic solidparticles, preferably pigments, a binder, and an additive. A preferredpigment is one selected from the group consisting of calcium carbonate,kaolin, talc, silicate, a plastic pigment, and titanium oxide. Apreferred kaolin is calcinated kaolin. A preferred calcium carbonate isone selected from a group consisting of marble, chalk and a precipitatedcalcium carbonate (PCC) or a combination of at least two thereof. Apreferred silicate is a layer silicate. A preferred plastic pigment isspherical, preferably in the shape of a hollow sphere. A preferredbinder is one selected from the group consisting of styrene-butadiene,acrylate, acrylonitrile, starch and polyvinyl alcohol or a combinationof at least two thereof, wherein acrylate is preferred. A preferredstarch is one selected from the group consisting of cationicallymodified, anionically modified, and fragmented, or a combination of atleast two thereof. A preferred additive is one selected from the groupconsisting of a rheology modifier, a shading dye, an optical brightener,a carrier for an optical brightener, a flocculent, a deaerating agent,and a surface energy modifier, or a combination of at least two thereof.A preferred deaerating agent is a coating colour deaerating agent,preferably based on silicone or on fatty acids, or both. A preferredsurface energy modifier is a surfactant.

Carrier Layer

As a carrier layer, any material deemed suitable by the person skilledin the art may be used, which has sufficient strength and stiffness togive the container enough stability to ensure that the container in thefilled state substantially retains its shape. In addition to a number ofplastics, plant fibres, in particular pulp, preferably glued, bleachedand/or unbleached pulp are preferred, with paper and cardboard beingparticularly preferred. The weight per unit area of a carrier layer,preferably of each carrier layer, is preferably in a range from 120 to450 g/m², particularly preferably in a range from 130 to 400 g/m² andmost preferably in a range from 150 to 380 g/m². A preferred cardboardusually has a single- or multi-layer structure and may be coated on oneor both sides with one or even several cover layers. Further, a suitablecardboard has a residual moisture of less than 20% by weight, preferablyfrom 2 to 15% by weight and particularly preferably from 4 to 10% byweight, relative to the weight of the cardboard. A particularlypreferred cardboard has a multi-layer structure. Further, the cardboardpreferably has, on the surface facing the environment, at least one,preferably, however, at least two layers of a cover layer, known to theperson skilled in that art as a “coating”. Further, a preferredcardboard has a Scott Bond value in a range from 100 to 360 J/m²,preferably from 120 to 350 J/m² and particularly preferable from 135 to310 J/m². The ranges specified above make it possible to provide acomposite from which a container with high impermeability can be foldedeasily and within small tolerances. A preferred carrier layer comprisesat least a surface, with preferably a cover layer on each of twoopposite surfaces. Each carrier layer preferably comprises a cover layeron each surface, unless this is expressly excluded. Most preferably,each carrier layer does not comprise a cover layer only on one peeledsurface, if there is one. Preferably, the first carrier layer and thesecond carrier layer are formed in one piece. More preferably, the firstcarrier layer and the second carrier layer and the third carrier layerare formed in one piece. Still more preferably, the first carrier layerand the second carrier layer and the third carrier layer and the fourthcarrier layer are formed in one piece. Most preferably, all carrierlayers are formed in one piece.

Barrier Layer

As a barrier layer, any material deemed suitable by the person skilledin the art may be used, which has a sufficient barrier effect, inparticular against oxygen. The barrier layer is a plastic barrier layer.The barrier layer comprises at least 70% by weight, more preferably atleast 80% by weight and most preferably at least 95% by weight of atleast one plastic, which is known to the person skilled in the art forthis purpose, especially on account of aroma and gas barrier propertiesthat are suitable for packaging containers. As such plastics, alsoreferred to as barrier plastics in this document, consideration is givento N or O bearing plastic, in particular thermoplastic plastics, bothindividually and in mixtures of two or more. According to the invention,it may prove advantageous if the plastic barrier layer has a meltingtemperature in a range from more than 155 to 300° C., preferably in arange from 160 to 280° C. and more preferably in a range from 170 to270° C.

Further, the plastic barrier layer is preferably thermoplastic. Morepreferably, the plastic barrier layer has a weight per unit area in arange from 2 to 120 g/m², preferably in a range from 3 to 60 g/m², morepreferably in a range from 4 to 40 g/m² and most preferably in a rangefrom 6 to 30 g/m². Further, the plastic barrier layer is preferablyobtainable through melting, for example through extrusion, in particularlayer extrusion. In addition, the plastic barrier layer may preferablybe introduced into the sheet-like composite through lamination.According to another embodiment, plastic barrier layers can also beselected which can be obtained through separation from a solution ordispersion of plastics.

Preferably, suitable polymers are those which have a molecular weightwith a weight average, determined by gel permeation chromatography (GPC)by means of light scattering, in a range from 3×10³ to 1·10⁷ g/mol,preferably in a range from 5·10³ to 1·10⁶ g/mol and more preferably in arange from 6·10³ to 1·10⁵ g/mol. As suitable polymers, consideration isgiven to, in particular, polyamide (PA) or polyethylene vinyl alcohol(EVOH) or a mixture thereof.

All PAs that appear suitable to the person skilled in the art for theuse according to the invention are eligible as polyamides, among whichthermoplastic PAs are particularly preferred. PA 6, PA 6.6, PA 6.10, PA6.12, PA 11 or PA 12 or a mixture of at least two thereof deserveparticular attention, PA 6 and PA 6.6 being particularly preferred andPA 6 most preferred. PA 6 are commercially available, for example, underthe trade names Akulon®, Durethan® and Ultramid®. In addition, amorphouspolyamides, such as MXD6, Grivory® and Selar® PA are suitable. It isfurther preferred that the PA has a density in a range from 1.01 to 1.40g/cm³, preferably in a range from 1.05 to 1.30 g/cm³ and more preferablyin a range from 1.08 to 1.25 g/cm³. Further, it is preferred that the PAhas a viscosity count in a range from 130 to 185 ml/g and preferably ina range from 140 to 180 ml/g.

All EVOHs that appear suitable to the person skilled in the art for theuse according to the invention are eligible as EVOHs, among whichthermoplastic EVOHs are particularly preferred. Examples arecommercially available, inter alia, under the trade names EVAL™ of EVALEurope NV, Belgium in a plurality of different embodiments, for examplethe varieties EVAL™ F104B or EVAL™ LR171B. Preferred EVOHs have at leastone, two, several or all of the following properties:

-   -   an ethylene content in a range from 20 to 60 mol-%, preferably        from 25 to 45 mol-%;    -   a density in a range from 1.0 to 1.4 g/cm³, preferably from 1.1        to 1.3 g/cm³;    -   a melting point in a range from more than 155 to 235° C.,        preferably from 165 to 225° C.;    -   an MFR value (210° C./2.16 kg, if T_(S(EVOH))<230° C.; 230°        C./2.16 kg, if 210° C.<T_(S(EVOH))<230° C.) in a range from 1 to        25 g/10 min, preferably from 2 to 20 g/10 min;    -   an oxygen permeation rate in a range from 0.05 to 3.2 cm³·20        μm/m²·day·atm, preferably in a range from 0.1 to 1 cm³·20        μm/m²·day·atm.

Preferably, a layer selected from the group consisting of the firstbarrier layer, the second barrier layer, the third barrier layer and thefourth barrier layer, or a combination of at least two thereof,preferably all, does not contain aluminium in a proportion of more than50% by weight, preferably of more than 40% by weight, more preferably ofmore than 30% by weight, more preferably of more than 20% by weight,more preferably of more than 10% by weight, more preferably of more than5% by weight, more preferably of more than 1% by weight, more preferablyof more than 0.5% by weight, most preferably of more than 0.05% byweight, in each case relative to the weight of the barrier layerconcerned.

The first barrier layer and the second barrier layer are preferablyformed in one piece. More preferably, the first barrier layer and thesecond barrier layer and the third barrier layer are formed in onepiece. Still more preferably, the first layer and the second barrierlayer and the third barrier layer and the fourth barrier layer areformed in one piece. Most preferably, all barrier layers are formed inone piece.

Polymer Layers

There is preferably a polymer layer between the first carrier layer andthe first barrier layer, also preferably between the second carrierlayer and the second barrier layer, also preferably between the thirdcarrier layer and the third barrier layer, and also preferably betweenthe fourth carrier layer and the fourth barrier layer. Further, thefirst barrier layer is preferably overlaid by a polymer layer on a sidefacing the first carrier layer, preferably bonded with the polymerlayer. Further, the second barrier layer is preferably overlaid by apolymer layer on a side facing the second carrier layer, preferablybonded with the polymer layer. Further, the third barrier layer ispreferably overlaid by a polymer layer on a side facing the thirdcarrier layer, preferably bonded with the polymer layer. Further, thefourth barrier layer is preferably overlaid by a polymer layer on a sidefacing the fourth carrier layer, preferably bonded with the polymerlayer. Further, the first carrier layer is preferably overlaid by apolymer layer on a side facing the first barrier layer, preferablybonded with the polymer layer, in which case the first carrier layer ispreferably not bonded with the polymer layer on the side facing thefirst barrier layer in the first wall region. Further, the secondcarrier layer is preferably overlaid by a polymer layer on a side facingthe second barrier layer, preferably bonded with the polymer layer, inwhich case the second carrier layer is preferably not bonded with thepolymer layer on the side facing the second barrier layer in the firstwall region and the second wall region. Further, the third carrier layeris preferably overlaid by a polymer layer on a side facing the thirdbarrier layer, preferably bonded with the polymer layer. Further, thefourth carrier layer is preferably overlaid by a polymer layer on a sidefacing the fourth barrier layer, preferably bonded with the polymerlayer.

Each polymer layer may comprise further components. These polymer layersare preferably introduced into or applied to the layer sequence in anextrusion process. The further components of the polymer layers arepreferably components which do not adversely affect the behaviour of thepolymer melt when applied as a layer. The further components may beinorganic compounds, such as metal salts, or further plastics, such asfurther thermoplastic plastics. However, it is conceivable that thefurther components are fillers or pigments, for example carbon black ormetal oxides. Suitable thermoplastic plastics for the further componentsare considered in particular to be those which are easy to work due togood extrusion behaviour. Among these, polymers obtained by means ofchain polymerisation, in particular polyester or polyolefin, aresuitable, with cyclic olefin-copolymers (COC), polycyclicolefin-copolymers (POC), in particular polyethylene and polypropylene,being particularly preferred and polyethylene most preferred. Among thepolyethylenes, HDPE, MDPE, LDPE, LLDPE, VLDPE and PE as well as mixturesof at least two thereof are preferred. Mixtures of at least twothermoplastic plastics may also be used. Suitable polymer layers have amelt flow rate in a range from 1 to 25 g/10 min, preferably in a rangefrom 2 to 20 g/10 min and most preferably in a range from 2.5 to 15 g/10min, and a density in a range from 0.890 g/cm³ to 0.980 g/cm³,preferably in a range from 0.895 g/cm³ to 0.975 g/cm³, and morepreferably in a range from 0.900 g/cm³ to 0.970 g/cm³. The polymerlayers preferably have a melting temperature at least in a range from 80to 155° C., preferably in a range from 90 to 145° C. and most preferablyin a range from 95 to 135° C. A preferred polymer layer is a polyolefinlayer, preferably a polyethylene layer, or a polypropylene layer, orboth.

Polyolefin

A preferred polyolefin is a polyethylene, or a polypropylene, or both. Apreferred polyethylene is one selected from the group consisting of anLDPE, an LLDPE, and an HDPE, or a combination of at least two thereof. Afurther preferred polyolefin is an mPolyolefin. Suitable polyethyleneshave a melt flow rate (MFR) in a range from 1 to 25 g/10 min, preferablyin a range from 2 to 20 g/10 min and most preferably in a range from 2.5to 15 g/10 min, and a density in a range from 0.910 g/cm³ t 0.935 g/cm³,preferably in a range from 0.912 g/cm³ to 0.932 g/cm³, and morepreferably in a range from 0.915 g/cm³ to 0.930 g/cm³.

mPolyolefin

An mPolyolefin is a polyolefin which is produced by means of ametallocene catalyst. A metallocene is a metallic organic compound inwhich a central metal atom is arranged between two organic ligands, suchas cyclopentadienyl ligands, for example. A preferred mPolyolefin is anmPolyethylene, or an mPolypropylene, or both. A preferred mPolyethyleneis one selected from the group consisting of an mLDPE, an mLLDPE, and anmHDPE, or a combination of at least two thereof.

Melting Temperatures

A preferred mPolyolefin is characterised by at least a first meltingtemperature and a second melting temperature. Preferably, themPolyolefin is characterised by a third melting temperature in additionto the first and second melting temperature. A preferred first meltingtemperature lies in a range from 84 to 108° C., preferably from 89 to103° C., more preferably from 94 to 98° C. A preferred further meltingtemperature lies in a range from 100 to 124° C., preferably from 105 to119° C., more preferably from 110 to 114° C.

Adhesion/Adhesion Promoting Layer

There may be an adhesion promoting layer between layers of the wallwhich do not abut directly against each other. In particular, there maybe an adhesion promoting layer between each n^(th) barrier layer and apolymer layer which overlays the n^(th) barrier layer on a side facingthe n^(th) carrier layer, where n is an integer in a range from 1 to 4.

Adhesion promoters in an adhesion promoting layer are considered to beall plastics which, through functionalisation by means of suitablefunctional groups, are suitable for generating a fixed connectionthrough the formation of ionic bonds or covalent bonds with a surface ofan adjoining layer. These are functionalised polyolefins, obtainedthrough co-polymerisation of ethylene with acrylic acids, such asacrylic acid, methacrylic acid, crotonic acid, acrylates, acrylatederivatives, or carboxylic acid anhydrides bearing double bonds, forexample maleic anhydride, or at least two thereof. Among these,polyethylene maleic anhydride grafted polymers (EMAH), ethylene acrylicacid copolymers (EAA) or ethylene methacrylic acid copolymers (EMAA) arepreferred, which are sold, for example, by ExxonMobile Chemicals throughDuPont or Escor®6000ExCo under the trade names Bynel® andNucrel®0609HSA.

According to the invention, it is preferable that the adhesion between acarrier layer, a polymer layer or a barrier layer and the next layer isat least 0.5 N/15 mm, preferably at least 0.7 N/15 mm and morepreferably at least 0.8 N/15 mm. In an embodiment according to theinvention, it is preferable that the adhesion between a polymer layerand a barrier layer is at least 0.3 N/15 mm, preferably at least 0.5N/15 mm and more preferably at least 0.7 N/15 mm. Further, it ispreferable that the adhesion between a barrier layer and a polymer layeris at least 0.8 N/15 mm, preferably at least 1.0 N/15 mm and morepreferably at least 1.4 N/15 mm. In the event that a barrier layerindirectly follows a polymer layer via an adhesion promoting layer, itis preferable that the adhesion between the barrier layer and theadhesion promoting layer is at least 1.8 N/15 mm, preferably at least2.2 N/15 mm and more preferably at least 2.8 N/15 mm. In a specialembodiment, the adhesion between the individual layers is so strongthat, in the adhesion test, the carrier layer tears and, if cardboard isused as the carrier layer, the cardboard tears.

In One Piece

Two layers are formed in one piece if there is a transitional area inwhich the two layers abut against each other and merge into one anotherwithout an intermediate layer and without a connecting element. Apreferred transitional area is a fold region. A fold region comprises afold. A preferred fold runs along a crease. Layers formed in one piecehave preferably been manufactured together from raw materials as onepiece and have not been joined together following manufacture. Layersformed in one piece preferably have the same composition, or the samestructure, or both.

Container Precursor

A preferred container precursor is shell-shaped or tubular, or both. Ashell-shaped container precursor is preferably characterised in that itsouter surface corresponds to a geometrical shell surface. A tubularcontainer precursor is preferably a semi-endless tube structure with anopening on opposite ends of the tube.

Container

The closed container according to the invention may have a variety ofdifferent forms, but is preferably a substantially rectangularstructure. Furthermore, the container may be formed from a sheet-likecomposite, or have a 2- or multi-piece construction. In a multi-piececonstruction, it is conceivable that, in addition to the sheet-likecomposite, other materials are used, such as plastic, which can be usedin particular in the head or bottom portion of the container. In thiscase, however, it is preferred that the container is constructed for atleast 50%, more preferably at least 70% and even more preferably up toat least 90% of the area from the sheet-like composite. Furthermore, thecontainer pay comprise a device for emptying the contents. This can beformed, for example, from plastic and mounted on the outside of thecontainer. It is also conceivable that the device is integrated into thecontainer by direct injection moulding. According to a preferredembodiment, the container of the invention has at least one, preferablyfrom 4 to 22 or more edges, particularly preferably 7 to 12 edges. Edgeare understood in the context of the present invention as areasresulting from the folding of a surface. Examples of edges are theelongated contact areas of two wall surfaces of the container. In thecontainer, the container walls preferably represent the surfaces of thecontainer framed by the edges.

Peeling

Peeling is a process step known to the person skilled in the art toreduce the layer thickness of a layer, preferably a carrier layer, morepreferably a carrier layer selected from the group consisting ofcardboard, paperboard, and paper, or a combination of at least twothereof. Peeling is preferably carried out using a metal-removing tool,or a cutting tool, or both. A further preferred metal-removing tool is arotating tool. A most preferred rotating tool is a knife, preferably apot knife, or a milling tool, or both. A further preferredmetal-removing tool is a knife, preferably a rotating knife, mostpreferably a pot knife, or a milling tool, or both.

Folding the Sheet-Like Composite or the Wall

The folded area of the wall or of the sheet-like composite is preferablyfolded in a temperature range from 10 to 50° C., preferably in a rangefrom 15 to 45° C., and more preferably in a range from 20 to 40° C. Thiscan be achieved if the sheet-like composite or the wall has atemperature in the aforementioned ranges. Further, a folding tool,preferably together with sheet-like composite or the wall, preferablyhas a temperature in the aforementioned ranges. For this, the foldingtool does not have a heater. Rather, the folding tool, or the sheet-likecomposite and the wall, or both, can be cooled. Further it is preferredthat folding is carried out at a temperature of no more than 50° C. ascold-folding and that connecting is carried out at a temperature of over50° C., preferably over 80° C. and more preferably over 120° C. asheat-sealing. The foregoing conditions, in particular the temperatures,also preferably apply in the vicinity of the folding, for example, inthe housing of the folding tool. Further, the cold-folding, or thecold-folding in combination with the heat-sealing, is preferably appliedat fold-forming angles μ less than 100°, preferably less than 90°, morepreferably less than 70° and most preferably less than 50°. The angle μis formed between two adjoining fold surfaces.

Folding according to the invention is understood to mean a process inwhich an elongated, angle-forming crease is generated in the foldedsheet-like composite or the wall preferably by means of a folding edgeof a folding tool. For this, frequently two adjoining surfaces of asheet-like composite or the wall must be increasingly bent towards oneanother. The folding gives rise to at least two adjoining foldingsurfaces, which can then be connected, at least partially, to form acontainer area. According to the invention, the connection can be madeusing any measure that appears suitable to the person skilled in the artwhich enables as gas-tight and water-tight a connection as possible tobe formed.

Further, the fold surfaces preferably form an angle μ of less than 90°,preferably less than 45° and more preferably less than 20°. Frequently,the fold surfaces are folded to the extent that they come to lie on topof each other at the end of the fold. This is particularly advantageous,if the overlaying folds are then connected together to form the base ofthe container floor and the head of the container, which is oftenstructured in the form of a gable or flat. Regarding the gablearrangement, reference is made to WO 90/09926 A2 by way of example.

Closing Tool

A preferred closing tool is formed to create a seal. A further preferredclosing tool comprises at least an outlet opening for a hot gas. Afurther preferred closing tool comprises a sonotrode, or an anvil, orboth.

Longitudinal Seam

The first wall region and the second wall region and preferably also thethird wall region preferably belong to a longitudinal seam of thecontainer precursor, or of the closed container. The first wall regionand the second wall region and preferably also the third wall regionpreferably form a longitudinal seam of the container precursor, or ofthe closed container.

Food

Food is considered to be all food for human consumption and animal feedknown to the person skilled in the art. Preferred foods are liquid above5° C., for example milk products, soups, sauces, non-carbonated drinks.The container or the container precursor can be filled in various ways.On the one hand, the food and the container or the container precursorcan be sterilised as far as possible, separately, prior to filling,through suitable measures, such as through treatment of the container orthe container precursor with H₂O₂, UV radiation, or other suitablehigh-energy radiation, plasma treatment, or a combination of it leasttwo of these measures, as well as through heating the food and thenpouring it into the container. This type of filling is frequentlyreferred to as aseptic filling and is preferred according to theinvention. In addition to, or in place of, aseptic filling, heating thecontainer or the container precursor after it has been filled with foodto reduce the number of bacteria is widespread. This is done preferablythrough pasteurisation or autoclaving. With this process, less sterilefood and containers or container precursors can be used.

Hole/Opening Aid

To facilitate the opening of the closed container of the invention, acarrier layer may comprise at least one hole. In a special embodiment,the hole is overlaid by at least a barrier layer and preferably apolymer layer as hole-cover layers. Further, one or several furtherlayers, in particular adhesion promoting layers, can be provided betweenthe abovementioned layers. In this case, the hole-cover layers arepreferably connected together at least partially, preferably for atleast 30%, preferably for at least 70%, and more preferably for at least90% of the surface formed by the hole. According to a specialembodiment, it is preferred that the hole penetrates the entire wall andis covered by the closing device closing the hole or the opening device.In connection with a preferred embodiment, the hole provided in thecarrier layer may have any form known to the person skilled in the artand one that is suitable for various closures, drinking straws oropening aids. Usually, a closed container is opened by means of the, atleast partial, destruction of the hole-cover layers covering the hole.This destruction may take place through cutting, pressing into thecontainer, or pulling out of the container. The destruction may takeplace by means of an openable closing device or a drinking strawconnected to the container and arranged in the area of the hole, usuallyabove the hole.

According to a further preferred embodiment, a carrier layer of the wallcomprises a plurality of holes in the form of a perforation, theindividual holes being covered at least by a barrier layer, andpreferably a polymer layer, as hole-cover layers. A containermanufactured from such a composite can then be opened by tearing alongthe perforations. Such holes for perforations are preferably created bymeans of a laser. The use of laser beams is particularly preferred if ametal foil or a metalised foil is used as a barrier layer. Further, itis possible for the perforation to be created by mechanical perforationtools, usually having blades.

According to a further preferred embodiment, the wall or the sheet-likecomposite is subjected to heat treatment at least in the area of the atleast one hole. If there are several holes in the form of a perforationin the carrier layer, it is particularly preferred to carry out thisheat treatment also around the edge of the hole. The heat treatment maybe carried out through radiation, through hot gas, through a solids heatcontact, through mechanical vibrations, preferably through ultrasound,or through a combination of at least two of these measures. Heattreatment is particularly preferably carried out through radiation,preferably electromagnetic radiation and, particularly preferably,electromagnetic induction or also through hot gas. The optimal operatingparameters to be chosen are known to the average person skilled in theart.

Radiation

In the case of radiation, any type of radiation deemed suitable by theperson skilled in the art for softening the plastics of the polymerlayers is taken into consideration. Preferred types of radiation are IRrays, UV rays, and microwaves. In the case of IR waves, which are alsoused for the IR welding of sheet-like composites, wavelengths are in arange from 0.7 to 5 μm. Further, laser beams in a wavelength range from0.6 to less than 1.6 μm can be used. In connection with the use of IRrays, these are generated by various suitable emitters known to theperson skilled in the art. Short-wave emitters in a range from 1 to 1.6μm are preferably halogen emitters. Medium-wave emitters in a rangefrom >1.6 to 3.5 μm are, for example, metal-foil emitters. Quartzemitters are frequently used as long-wave emitters in a range>3.5 μm.Lasers are used increasingly often. Diode lasers in a wavelength rangefrom 0.8 to 1 μm, Nd:YAG lasers at approximately 1 μm, and CO₂—Laserlasers at approximately 10.6 μm, are used. High-frequency technologieswith a frequency range from 10 to 45 MHz are frequently used in anoutput range from 0.1 to 100 kW.

Ultrasound

In the case of ultrasound, the following treatment parameters arepreferred:

-   P1 a frequency in a range from 5 to 100 kHz, preferably in a range    from 10 to 50 kHz and more preferably in a range from 15 to 40 kHz;-   P2 an amplitude in a range from 2 to 100 μm, preferably in a range    from 5 to 70 μm kHz and more preferably in a range from 10 to 50 μm;-   P3 period of vibration (i.e. the period of time in which a vibrating    body such as a sonotrode or inductor acts on the sheet-like    composite like a contact rocker) in a range from 50 to 1000 msec,    preferably in a range from 100 to 600 msec, and more preferably in a    range from 150 to 300 msec.

For the appropriate selection of radiation or vibration conditions, itis advantageous to consider the internal resonances of the plastics andto select frequencies that are close to them.

Contact with a Solid

Heating via contact with a solid may take place, for example, through ahotplate or hot mould that is in direct contact with the sheet-likecomposite, which transmits heat to the sheet-like composite.

Hot Gas

Hot gas, preferably hot air, may be directed at the sheet-like compositeby means of suitable fans, outlet openings or nozzles, or a combinationthereof. Frequently, a contact heater and hot gas are usedsimultaneously. For example, a holding device for a tube formed from thesheet-like composite, through which hot gas has flowed and which hastherefore been heated, and which transmits the hot gas through suitableopenings, may heat the sheet-like composite through contact with thewall of the holding device and the hot gas. Further, the tube may beheated by fixing it to a tube bracket and by passing hot gas through theareas of the tube to be heated by means of one or two or more hot gasnozzles provided in the shroud support.

Sterilisation

Sterilisation describes the treatment of a product, preferably acontainer, or a food, or both, in order to reduce the number of bacteriaon or in the product. Sterilisation may, for example, take place throughthe application of heat or through contact with a chemical. The chemicalcan be gaseous, or liquid, or both. A preferred chemical is hydrogenperoxide.

Autoclaving

Autoclaving describes the treatment of a product, usually a filled andclosed container, wherein the product is in a pressure chamber and isheated to a temperature of more than 100° C., preferably between 100 and140° C. In addition, the chamber pressure in the pressure chamber isabove 1 bar, preferably above 1.1 bar, more preferably above 1.2 bar,more preferably above 1.3 bar, and up to 4 bar. Further, autoclaving ispreferably carried out with the product in contact with water vapour.

Pasteurisation

Pasteurisation describes the rapid heating of liquid or pasty foodstuffsto temperatures of up to 100° C. to kill, or inhibit the growth of,micro-organisms. It is used to increase the shelf-life of, inter alia,milk, fruit and vegetable juice, and liquid ice.

Measurement Methods

The following measurement methods were used in the context of theinvention. Unless otherwise stated, the measurements were carried out atan ambient temperature of 25° C., an ambient air pressure of 100 kPa(0.986 atm) and a relative humidity of 50%.

MFR Value

The MFR value is measured in accordance with standard ISO 1133 (unlessspecified otherwise at 190° C. and 2.16 kg).

Density

Density is measured in accordance with standard Norm ISO 1183-1.

Melting Temperature

The melting temperature is determined on the basis of DSC Method ISO11357-1, -5. Equipment calibrations are carried out in accordance withmanufacturers' specifications on the basis of the followingmeasurements:

-   -   Indium temperature—Onset temperature,    -   Indium heat of fusion,    -   Zinc temperature—Onset temperature.        Oxygen Permeation Rate

The oxygen permeation rate is determined in accordance with standard ISO14663-2 Annex C at 20° C. and 65% relative humidity.

Moisture Content of the Cardboard

The moisture content of the cardboard is measured in accordance withstandard ISO 287:2009.

Adhesion

To determine the adhesion of two adjacent layers, they are fixed to a90° Peel Test Device, manufactured, for example, by Instron “Germanrotating wheel fixture”, on a rotating cylinder, which rotates at 40mm/min during the measurement. The samples are cut into 15 mm broadstrips beforehand. On one side of the sample, the layers are separatedfrom each other and the detached end is clamped in a tensile testingdevice directed vertically upwards. A measuring device is mounted on thetensile testing device to determine the tensile force. When the cylinderis rotated, the force that is necessary to separate the layers from eachother is measured. This force corresponds to the adhesion of the layersto each other and is given in N/15 mm. The individual layers can beseparated, for example, mechanically or through targeted pre-treatment,such as allowing the sample to soften for 3 min in 60° C., 30% aceticacid.

Molecular Weight Distribution

Molecular weight distribution is measured using gel permeationchromatography by means of light scattering: ISO 16014-3/-5.

Viscosity Number of PA

The viscosity number of PA is measured in accordance with standard ISO307 in 95% sulphuric acid.

Layer Thickness

A sample measuring approximately 2.5 to 3.0 cm×1.0 to 1.5 cm is takenfrom the composite material to be examined. The long side of the sampleis placed transversely to the direction of the extrusion and to thedirection of the fibre of the cardboard. The sample is fixed in a metalclamp, which forms a smooth surface. The sample should not protrude morethan 2 to 3 mm. The metal clamp is fixed prior to cutting. In order toobtain a clean cut, especially of the cardboard fibres, the part of thesample protruding from the metal clamp is frozen with cold spray. Thisis then removed using a disposable blade (Leica, Microtome Blades). Thehold of the sample in the metal clamp is now eased to such an extentthat the sample can be pushed approximately 3 to 4 mm out of the metalclamp. It is then fixed again. For examination under the lightmicroscope (Nicon Eclipse E800), the sample is placed in the sampleholder on the object plate of the light microscope under one of thelenses (magnification ×2.5; ×5; 33 10; ×20; ×50). The appropriate lensis chosen on the basis of the layer thickness of the layer of the areato be examined. Precise centring is carried out during microscopy. Inmost cases side lighting (swan-neck lights) is used as the source light.If necessary, the incident-light illuminator of the light microscope isused in addition or alternatively. If the sample is optimally sharpenedand illuminated the individual layers of the composite should berecognisable. An Olympus camera (Olympus DP 71) with suitable imageprocessing software (analySIS) by Analysis is used for documentation andmeasurements. It is also used to determine the layer thickness of theindividual layers.

Compression Test

For this test, 5 containers are manufactured and filled with waterbefore the process step of folding the container precursor and beforethe process step of closing the container precursor. The purpose of thetest is to determine the compressive strength along the longitudinalaxis of the container. It may also be used to assess the resilience offilled containers in the static case of storage and in the dynamic caseof transportation. The compression test is carried out on the individualcontainers in accordance with DIN EN ISO12048. The preceding storage ofthe containers is carried out in accordance with DIN EN ISO 2233:2000.The measuring device used is TIRAtest 28025 (Tira GmbH; EisfelderStrasse 23/25; 96528 Schalkau, Germany). The mean value of the maximumbreaking load (load value) is determined. This describes the value thatleads to the failure of the containers.

The invention is presented in more detail below through examples anddrawings. The examples and drawings do not signify any limitation of theinvention.

For the examples (according to the invention) and the comparativeexamples (not according to the invention), laminates with the followinglayer structure and layer sequence were generated through a layerextrusion process.

Layer structure/ Weight per layer sequence unit area Index LDPE 15 g/m²(3) Carrier layer 240 g/cm² (2) Barrier layer 8 g/m² (1) Adhesionpromotion layer 4 g/m² (5) LDPE 22 g/m² (3) mPE blend 10 g/m² (4)

The details of the above indices are:

-   -   (1) Durethan B31F, Lanxess, Cologne, Germany    -   (2) Cardboard: Stora Enso Natura T Duplex Doppelstrich, Scott        bond 200 J/m², residual moisture content 7.5%    -   (3) LDPE 19N430 from Ineos GmbH, Cologne    -   (4) m-PE Blend: 35% by weight Affinity® PT 1451G1 from Dow        Chemicals and 65% by weight LDPE 19N430 from Ineos GmbH, Cologne    -   (5) Yparex 9207, Yparex, 7521 BG Enschede, Netherlands

The geometries of the longitudinal seam summarised in Table 1 below weregenerated in the examples (according to the invention) and thecomparative examples (not according to the invention). In Table 1 thesmaller thickness of a carrier layer means that this carrier layer waspeeled. Peeled carrier layers have a thickness of 230 μm. The largerthickness of the carrier layer means that this carrier layer, with thelarger thickness, is unpeeled. If all the carrier layers of a laminateare of equal thickness, this means that all the carrier layers areunpeeled. Unpeeled carrier layers have a thickness of 430 μm.

TABLE 1 Longitudinal seam geometries according to the examples andcomparative examples Thicknesses of the carrier Thicknesses of thecarrier Existence of a third wall layers in the first wall layers in thesecond wall region (301) in the region (103) region (104) longitudinalseam Comparative first (205) = third (209) first (205) = third (209) noexample 1 Comparative second (206) < first (205) = second (206) = first(205) = no example 2 third (209) third (209) Example 1 second (206) <first (205) = second (206) < first (205) = no third (209) third (209)Example 2 second (206) = first (205) < second (206) = first (205) < nothird (209) third (209) Example 3 second (206) < first (205) = second(206) = first (205) < no third (209) third (209) Example 4 second (206)< first (205) = second (206) = first (205) < yes third (209) third (209)

In comparative example 1 none of the carrier layers in the longitudinalseam was peeled. Accordingly, for the longitudinal seam, no seam wasgenerated through the folding of the laminate and the laminate foldingover on itself. There is, therefore, no second carrier layer (206) whichis generated by the folding. As there is no peeling, the first wallregion (103) and the second wall region (104) are identical. In alongitudinal seam according to comparative example 1, there is no thirdwall region (301), in which the first wall layer (201), which containsthe first carrier layer (205), is connected directly to the third walllayer (203), which contains the third carrier layer (209). In FIG. 8,this seam geometry is demonstrated in a container precursor.

In comparative example 2, which is not according to the invention, thesecond carrier layer (206) was only peeled in a peripheral area. Thefold for folding the second wall layer (202) over onto the first walllayer (201) was generated in the unpeeled area of the second carrierlayer (206) in the unpeeled area lying further from the edge. Therefore,the second carrier layer (206) in the first wall region (103) is peeledand hence thinner than the first carrier (205), but, in the second wallregion (104), it is not peeled and hence as thick as the first carrierlayer (205). In a longitudinal seam according to comparative example 2,there is no third wall region (301), in which the first wall layer(201), which contains the first carrier layer (205), is connecteddirectly to the third wall layer (203), which contains the third carrierlayer (209). The seam geometry of comparative example 2 is illustratedin FIG. 11 in a container precursor.

In example 1 according to the invention, the second carrier layer (206)was peeled, and the peeled area was completely folded over onto thefirst carrier layer (205) to create a seam. Therefore, the secondcarrier layer (206) both in the first wall region (103) and in thesecond wall region (104) is thinner than the first carrier layer (205).Therefore, the first wall region (103) and the second wall region (104)are identical. In a longitudinal seam according to example 1, there isno third wall region (301), in which the first wall layer (201), whichcontains the first carrier layer (205), is connected directly to thethird wall layer (203), which contains the third carrier layer (209).The seam geometry of example 1 is demonstrated in FIG. 9 in a containerprecursor.

In example 2 according to the invention, the carrier material was peeledin a peripheral area of the laminate and the peeled area was folded sothat it could be completely folded over on itself. In this way, a peeledfirst carrier layer (205) was obtained, which was directly overlaid by apeeled second carrier layer (206) in a first wall region (103) and in asecond wall region (104). In a longitudinal seam according to example 2,there is no third wall region (301), in which the first wall layer(201), which contains the first carrier layer (205), is connecteddirectly to the third wall layer (203), which contains the third carrierlayer (209). The seam geometry of example 2 is demonstrated in FIG. 10in a container precursor.

Example 3 according to the invention was generated in the same way asexample 2, but the peeled second carrier layer (206) was folded overacross the peeled area of the first carrier layer (205) as far as theunpeeled area of the first carrier layer (205). This results in a firstwall region (103), in which a peeled second carrier layer (206) and anunpeeled third carrier layer (209) follow an unpeeled first carrierlayer (205). In the second wall region (104), according to example 3, apeeled second carrier layer (206) and an unpeeled third carrier layer(209) follow a peeled first carrier layer (205). In a longitudinal seamaccording to example 3, there is no third wall region (301), in whichthe first wall layer (201), which contains the first carrier layer(205), is connected directly to the third wall layer (203), whichcontains the third carrier layer (209). The seam geometry of example 3is demonstrated in FIG. 2 in a container precursor.

Example 4 according to the invention is like example 3, but here thethird wall layer (203) extends beyond the second wall layer (202) as faras the first wall layer (201). Therefore, there is a third wall region(301), in which the first wall layer (201), which contains the firstcarrier layer (205), is connected directly to the third wall layer(203), which contains the third carrier layer (209), in the longitudinalseam according to example 4. The seam geometry of example 4 isdemonstrated in FIG. 3 in a container precursor.

The containers according to the above examples (according to theinvention) and the comparative examples (not according to the invention)were examined as regards their stability according to the abovementionedcompression. Further, the defective container precursors produced aswell as the average process speed during the manufacturing process weredetermined.

TABLE 2 Container failure based on maximum breaking load (according toDIN EN ISO 12048), percentage of defective container precursors as wellas average process speed Maximum Percentage of defective breaking loadcontainer precursors Average process [N] [%] speed [m/min] Comparative110 45 180 example 1 Comparative 115 17 200 example 2 Example 1 150 12380 Example 2 163 1 510 Example 3 175 0 560 Example 4 197 0 580

As shown in Table 2, the containers manufactured in accordance with theexamples according to the invention are more stable than the containersof the comparative examples. The containers of examples 3 and 4 turnedout to be particularly advantageous. In addition, more defectivecontainer precursors are produced in the manufacturing process of thecontainers of the comparative examples. In the manufacture of thecontainers according to examples 3 and 4, the percentage of defectivecontainer precursors is 0%. Further, it is clear from Table 2 thatcontainers manufactured in accordance with the examples according to theinvention can be produced more quickly. The average process speed ishighest for examples 3 and 4. Overall, the results for example 4 are themost advantageous.

In the drawings:

FIG. 1a ) shows a schematic representation of a shell-shaped containerprecursor according to the invention;

FIG. 1b ) shows a schematic representation of a tubular containerprecursor according to the invention;

FIG. 2 shows a schematic cross section of a section of a wall of acontainer precursor according to the invention;

FIG. 3 shows a schematic cross section of a section of a wall of afurther container precursor according to the invention;

FIG. 4 shows a schematic cross section of a section of a wall in a headportion of a closed container according to the invention;

FIG. 5a ) shows a schematic illustration of a process step a) of aprocess according to the invention for manufacturing a containerprecursor;

FIG. 5b ) shows a schematic illustration of a process step b) of aprocess according to the invention for manufacturing a containerprecursor;

FIG. 5c ) shows a schematic illustration of a process step c) of aprocess according to the invention for manufacturing a containerprecursor;

FIG. 5d ) shows a schematic illustration of a process step d) of aprocess according to the invention for manufacturing a containerprecursor;

FIG. 5e ) shows a schematic illustration of a process step e) of aprocess according to the invention for manufacturing a containerprecursor;

FIG. 5f ) shows a schematic illustration of a process step f) of aprocess according to the invention for manufacturing a containerprecursor;

FIG. 6 shows a schematic representation of a closed container accordingto the invention;

FIG. 7 shows a flowchart of a process according to the invention for themanufacture of a closed container;

FIG. 8 shows a schematic cross section of a section of a wall of acontainer precursor that is not according to the invention;

FIG. 9 shows a schematic cross section of a section of a wall of afurther container precursor that is not according to the invention;

FIG. 10 shows a schematic cross section of a section of a wall of acontainer precursor that is not according to the invention; and

FIG. 11 shows a schematic cross section of a section of a wall of afurther container precursor that is not according to the invention.

FIG. 1a ) shows a schematic representation of a shell-shaped containerprecursor according to the invention 100. The container precursor 100comprises a wall 102, which consists of a sheet-like composite in onepiece. The container precursor surrounds an interior region 101. Anouter surface of the sheet-like composite forms a geometrical outersurface of a cube. A circumference 105 of this outer surface and henceof the container precursor is indicated by a thick dashed line. Thecontainer precursor is formed from the sheet-like composite by foldingat at least 4 folding locations. The end edges of the sheet-likecomposite are bonded together via sealing. This seal forms alongitudinal seam in the container precursor. The longitudinal seamcomprises a first wall region 103 and a second wall region 104. Thefirst wall region 103 has a width 106 of 3 mm along the circumference105. The second wall region 104 has a width 107 of 5 mm along thecircumference 105. Thin dashed lines in FIG. 1a ) represent creases inthe sheet-like composite. A head portion of a container precursor orcontainer may be formed by folding along the creases and by joiningcertain fold surfaces.

FIG. 1b ) shows a schematic representation of a tubular containerprecursor according to the invention 100. The container precursor 100comprises a wall 102, which consists of a sheet-like composite in onepiece. The container precursor surrounds an interior region 101. Thecontainer precursor 100 is a semi-endless tube structure with an openingat opposite ends of the tube. In FIG. 1b ) the length of the tube ispresented in shortened form.

FIG. 2 shows a schematic cross section of a section of a wall 102 of acontainer precursor according to the invention 100. The wall 102 is thewall 102 of the container precursor 100 in FIG. 1a ). In FIG. 2 theinterior region 101 below the wall 102 and hence in the containerprecursor 100 is presented. The cross section of FIG. 2 is a crosssection through the longitudinal seam of the container precursor 100.The wall 102 comprises a first wall region 103 and a second wall region104. The first wall region 103 and the second wall region 104 abutagainst each other. The first wall region 103 comprises a first layersequence, which comprises, as layers superimposed on each other from theinterior region 101 outwards, a first wall layer 201, a second walllayer 202 and a third wall layer 203. Each of these three wall layers201, 202, 203 belongs to the sheet-like composite. The first wall layer201 merges into the second wall layer 202 at the fold position shown inFIG. 2. In the first wall region 103 and in the second wall region 104,however, the three wall layers 201, 202, 203 do not merge into oneanother but, as described above, form a layer sequence in each wallregion 103, 104. Further, in the first wall region 103, the first walllayer 201 is connected to the second wall layer 202. Here, the secondwall layer 202 is sealed onto the first wall layer 201. Further, in thefirst wall region 103, the second wall layer 202 and the third walllayer 203 are connected to each other by means of a sealing connection.The first wall layer 201 comprises, as first wall layer sequence fromthe interior region 101 outwards, a first barrier layer 204 and a firstcarrier layer 205. The first barrier layer 204 is a plastic layercomprising, for 80% by weight relative to the weight of the firstbarrier layer 204, an EVOH (EVAL F104B von EVAL Europe. Zwijndrecht,Belgium) as barrier plastic and, for 20% by weight relative to theweight of the first barrier layer 204, Durethan B31F from Lanxess,Cologne. The first carrier layer 205 is a cardboard layer. There is apolyethylene layer (not shown) between the first barrier layer 204 andthe first carrier layer 205. The second wall layer 202 comprises, assecond wall layer sequence from the interior region 101 outwards, asecond carrier layer 206 and a second barrier layer 207. The secondbarrier layer 207 is a plastic layer comprising, for 80% by weightrelative to the weight of the second barrier layer 207, the above EVOHas barrier plastic and, for 20% by weight relative to the weight of thesecond barrier layer 207 Durethan B31F from Lanxess, Köln. The secondcarrier layer 206 is a cardboard layer. There is a polyethylene layer(not shown) between the second barrier layer 204 and the second carrierlayer 206. The third wall layer 203 comprises, as third wall layersequence from the interior region 101 outwards, a third barrier layer208 and a third carrier layer 209. The third barrier layer 208 is aplastic layer comprising, for 80% by weight relative to the weight ofthe third barrier layer 208, the above EVOH as barrier plastic and, for20% by weight relative to the weight of the third barrier layer 208Durethan B31F from Lanxess, Cologne. The third carrier layer 209 is acardboard layer. There is a polyethylene layer (not shown) between thethird barrier layer 208 and the third carrier layer 209. In the firstwall region 103 the second carrier layer 206 is a characterised by asmaller layer thickness than the first carrier layer 205 and the thirdcarrier layer 209. The layer thickness of the second carrier layer 206is 65% of the layer thickness of the first carrier layer 205 and of thethird carrier layer 209. The first carrier layer 205 and the thirdcarrier layer 209 have the same layer thickness in the first wall region103. The second wall region 104 comprises a second layer sequence with,as overlying layers seen from the interior region 101 outwards, theabove described first wall layer 201, the second wall layer 202 and thethird wall layer 203. In the second wall region 104 the second walllayer 202 and the third wall layer 203 are sealed one on top of theother. In the second wall region 104, the first wall layer 201 and thesecond wall layer 202 are neither connected together nor in contact witheach other. Between these two layers there is a cavity and no furtherlayer of the sheet-like composite. Further, in the second wall region104, the third carrier layer 209 is thicker than the second carrierlayer 206 and thicker than the first carrier layer 205. In the secondwall region 104, the layer thickness of the first carrier layer 205 andof the second carrier layer 206 is 65% of the layer thickness of thethird carrier layer 209. In the first wall region 103, the secondcarrier layer 206 is peeled, but the first carrier layer 205 is not. Inthe second wall region 104, the first carrier layer 205 and the secondcarrier layer 206 are peeled. All barrier layers 204, 207, 208 shown inFIG. 2 are designed in one piece with one another. These barrier layers204, 207, 208 belong to the sheet-like composite and merge into oneanother at folds. For the first barrier layer 204 and the second barrierlayer 207, this is shown with the fold in FIG. 2. Also, carrier layers205, 206, 209 shown in FIG. 2 are designed in one piece with oneanother. The carrier layers 205, 206, 209 belong to the sheet-likecomposite and merge into one another at folds. For the first carrierlayer 205 and the second carrier layer 206, this is shown with the foldin FIG. 2. Further folds of the sheet-like composite are not shown inFIG. 2 but can be derived from FIG. 1a ). To manufacture the wall 102 inFIG. 2, a carrier material (Stora Enso Natura T Duplex Doppelstrich fromStora Enso Oyj AG, Scott Bond value of 200 J/m², residual humidity 7.5%)with a “coating” on both carrier sides was used. Thus, both layersurfaces of each carrier layer 205, 206, 209 in FIG. 2 substantiallycompose a “coating”. However, peeled layer surfaces do not comprise a“coating”. Therefore, the layer surface of the first carrier layer 205facing the second carrier layer 206 in the second wall region 104 doesnot comprise a “coating”. In the first wall region 103, the layersurface of the first carrier layer 205 facing the second carrier layer206 comprises a “coating”. In the first wall region 103 as in the secondwall region 104, the layer surface of the second carrier layer 206facing the first carrier layer 205 does not comprise a “coating”. Allthe aforementioned polyethylene layers consist of LDPE 19N430 from IneosKöln GmbH. Along the circumference 105 (see FIG. 1a )) the first wallregion 103 has a first width 106 of 3 mm. The second wall region 104 hasa second width 107 of 5 mm along the circumference 105.

FIG. 3 shows a schematic cross section of a section of a wall 102 of afurther container precursor according to the invention 100. The wall 102is the wall 102 in FIG. 2, irrespective of the fact that the wall 102 inFIG. 3 additionally comprises a third wall region 301. The third wallregion 301 comprises a third layer sequence, comprising, as overlyinglayers seen from the interior region 101 outwards, the first wall layer201 and the third wall layer 203. The second wall layer 202 is notincluded in the third wall region 301. In the third wall region 301, thefirst wall layer 201 and the third wall layer 203 are sealed one on topof the other. The third wall region 301 abuts against the first wallregion 103. Along the circumference 105 (see FIG. 1a )) the third wall301 has a third width 302 of 5 mm. Further, in the second wall 104 thefirst wall layer 201 and the second wall layer 202 are not connectedtogether, but are partially in contact with each other. In particular,the first carrier layer 205 and the second carrier layer 206 in thesecond wall region are not connected together, but are partially incontact with each other.

FIG. 4 shows a schematic cross section of a section of a wall 102 in ahead portion of a closed container according to the invention 600. Thecontainer 600 was manufactured out of the container precursor in FIG. 1a), the head portion of the container 600 being obtained through foldsalong the creases and seals of specific fold surfaces shown in FIG. 1a). An external view of the closed container 600 is shown in FIG. 6. Thewall 102 is the wall 102 in FIG. 3, FIG. 4 showing a different sectionof the wall 102. The section of the wall 102 shown in FIG. 4 lies in thehead portion of the container 600. In this section, a further layer ofthe sheet-like composite is sealed on a side of the longitudinal seamfacing the interior region 101. Further, as shown in FIG. 6, thelongitudinal seam is folded over onto the head of the container.Therefore, the interior region 101 in FIG. 4 is in the lower part of theFigure. Without this folding over, in FIG. 4 there would be an outerspace in relation to the closed container 600 both above and below theshown connection. Thus, a fourth wall 401 is superimposed on the firstwall layer 201 on a side facing the interior region 101 in the firstwall region 103, the second wall region 104 and the third wall region301. The fourth wall layer 401, as a fourth wall layer sequence seenfrom the interior region 101 outwards, comprises a fourth carrier layer402 and a fourth barrier layer 403. The fourth barrier layer 403 is aplastic layer, comprising, for 80% by weight relative to the weight ofthe fourth barrier layer 403, an EVOH (EVAL F104B von EVAL Europe.Zwijndrecht, Belgium) as barrier plastic and, for 20% by weight relativeto the weight of the fourth barrier layer 403, Durethan B31F fromLanxess, Cologne. The fourth carrier layer 402 is a cardboard layer(Stora Enso Natura T Duplex Doppelstrich from Stora Enso Oyj AG, ScottBond value of 200 J/m², residual humidity 7.5%). There is a polyethylenelayer (not shown, LDPE 19N430 von der Ineos Köln GmbH) between thefourth barrier layer 403 and the fourth carrier layer 402. The fourthwall layer 401 also belongs to the sheet-like composite. The fourthbarrier layer 403 is formed as one piece with the first barrier layer204, the second barrier layer 207 and the third barrier layer 208. Allthese barrier 204, 207, 208, 403 belong to the sheet-like composite andmerge into each other at folds. The fourth carrier layer 402 is formedas one piece with the first carrier layer 205, the second carrier layer206 and the third carrier layer 209. All these carrier layers 205, 206,209, 402 belong to the sheet-like composite and merge into each other atfolds. The fourth carrier layer 402 has, in the first wall region 103,the second wall region 104 and the third wall region 301 the same layerthickness as the third carrier layer 209. Therefore, in the first wallregion 103, the second carrier layer 206 has a smaller layer thicknessthan the fourth carrier layer 402 and, in the second wall region 104,the fourth carrier layer 402 has a larger layer thickness than thesecond carrier layer 206 and the first carrier layer 205.

FIG. 5a ) shows a schematic illustration of a process step a) of aprocess according to the invention 500 for the manufacture of acontainer precursor 100. In process step a) a sheet-like composite isprovided. The sheet-like composite comprises a composite layer sequence501. The composite layer sequence 501 comprises, as overlying compositelayers, a composite carrier layer 505 and a composite barrier layer 504.The composite barrier layer 504 is a plastic layer, comprising, for 80%by weight relative to the weight of the composite barrier layer 504, anEVOH (EVAL F104B von EVAL Europe. Zwijndrecht, Belgium) as barrierplastic and, for 20% by weight relative to the weight of the fourthbarrier layer 403, Durethan B31F from Lanxess, Cologne. The compositecarrier layer 505 is a cardboard layer (Stora Enso Natura T DuplexDoppelstrich from Stora Enso Oyj AG, Scott Bond value of 200 J/m²,residual humidity 7.5%). There is a polyethylene layer (not shown, LDPE19N430 von der Ineos Köln GmbH) composite carrier layer 505 and thebarrier layer 504. The sheet-like composite can be split into an edgeregion 503 and an inner region 502. The end area 503 abuts against theinner region 502 at the dashed line in FIG. 5a ). In the inner region502, the sheet-like composite comprises a crease 515.

FIG. 5b ) shows a schematic illustration of a process step b) of aprocess according to the invention 500 for the manufacture of acontainer precursor 100. The process 500 is the same process 500 as inFIG. 5a ). The process step b) consists in reducing the layer thicknessof the composite carrier layer 505 in the edge region 503. Reductioninvolves peeling the composite carrier layer 505 with a rotating potknife. This is done with a peeling mechanism Model VN 50 from FortunaSpezialmaschinen GmbH, Weil der Stadt, Germany. In this way, the layerthickness of the composite carrier layer is reduced by 25% of theoriginal layer thickness.

FIG. 5c ) shows a schematic illustration of a process step c) of aprocess according to the invention 500 for the manufacture of acontainer precursor 100. The process 500 is the same process 500 as inFIG. 5a ). In process step c), a fold 506 is created in the end area503, and so a first edge fold region 507 and a further edge fold region508 are obtained. The first edge fold region 507 and the further edgefold region 508 abut against each other along the fold 506.

FIG. 5d ) shows a schematic illustration of a process step d) of aprocess according to the invention 500 for the manufacture of acontainer precursor 100. The process 500 is the same process 500 as inFIG. 5a ). The process step d) consists in bringing the first edge foldregion 507 into contact with a first part 509 of the further edge foldregion 508, and connecting a further part 510 of the further edge foldregion 508 to the inner region 502.

FIG. 5e ) shows a schematic illustration of a process step e) of aprocess according to the invention 500 for the manufacture of acontainer precursor 100. The process 500 is the same process 500 as inFIG. 5a ). The process step e) consists in creating a further fold 514along the crease 515 in the inner region 502 to obtain a first compositefold region 511 and a further composite fold region 512. The furthercomposite fold region 512 comprises a part 513 of the inner region 502.

FIG. 5f ) shows a schematic illustration of a process step f) of aprocess according to the invention 500 for the manufacture of acontainer precursor 100. The process 500 is the same process 500 as inFIG. 5a ). The process step f) consists in connecting the firstcomposite fold 511 to the first part 509 of the further edge fold region508 and the further part 510 of the further edge fold region 508 and thepart 513 of the inner region 502. Connection is carried out throughsealing. Sealing is carried out through bringing into contact, heatingup to sealing temperature and pressing. Heating is carried out throughblowing with hot air. Thus, in the process 500, the container precursor100 is manufactured through folding the sheet-like composite andcreating a longitudinal seam.

FIG. 6 shows a schematic representation of a closed container accordingto the invention 600. The closed container 600 is obtained throughfolding the container precursor 100 in FIG. 1a ) and closing the foldedcontainer precursor 100 through sealing with ultrasound. Sealing iscarried out using an ultrasound-transmitting sonotrode made of atitanium alloy and an anvil fixing the area to be sealed.

FIG. 7 shows a flowchart of a process according to the invention 700 forthe manufacture of a closed container 100 [sic]. The closed container600 in FIG. 6 may be manufactured through the process 700. The process700 comprises a process step a) 701: Provision of the containerprecursor 100 in FIG. 1a ). In a process step b) 702, the containerprecursor 100 is folded. In this way, a head portion and a bottomportion are formed. The head portion may, in particular, be formedthrough folding along the creases shown in FIG. 1a ). In a process stepc) 703, the head portion and the bottom portion of the folded precursor100 are closed through sealing with ultrasound. Sealing is carried outusing an ultrasound-transmitting sonotrode made of a titanium alloy andan anvil fixing the area to be sealed. Alternatively, the floor portioncan also be sealed using hot air.

FIG. 8 shows a schematic cross section of a section of a wall of acontainer precursor that is not according to the invention. The figureshows a geometry of a longitudinal seam 800 of the container precursorin cross section. The structure corresponds to comparative example 1.

FIG. 9 shows a schematic cross section of a section of a wall of acontainer precursor. The figure shows a geometry of a longitudinal seam900 of the container precursor in cross section. The structurecorresponds to example 1.

FIG. 10 shows a schematic cross section of a section of a wall of acontainer precursor. The figure shows a geometry of a longitudinal seam1000 of the container precursor in cross section. The structurecorresponds to example 2.

FIG. 11 shows a schematic cross section of a section of a wall of afurther container precursor that is not according to the invention. Thefigure shows a geometry of a longitudinal seam 1100 of the containerprecursor in cross section. The structure corresponds to comparativeexample 2.

LIST OF REFERENCE NUMBERS

-   100 container precursor according to the invention-   101 interior region-   102 wall-   103 first wall region-   104 second all area-   105 circumference-   106 first width-   107 second width-   201 first wall layer-   202 second wall layer-   203 third wall layer-   204 first barrier layer-   205 first carrier layer-   206 second carrier layer-   207 second barrier layer-   208 third barrier layer-   209 third carrier layer-   301 third wall region-   302 third width-   401 fourth wall layer-   402 fourth carrier layer-   403 fourth barrier layer-   500 process according to the invention for the manufacture of a    container precursor-   501 composite layer sequence-   502 inner region-   503 edge region-   504 composite barrier layer-   505 composite carrier layer-   506 Fold-   507 first edge fold region-   508 further edge fold region-   509 first part of the further edge fold region-   510 further part of the further edge fold region-   511 first composite fold region-   512 further composite fold region-   513 part of the inner region-   514 further fold-   515 Crease-   600 closed container according to the invention-   700 process according to the invention for the manufacture of a    closed container-   701 process step a)-   702 process step b)-   703 process step c)-   800 longitudinal seam according to comparative example 1-   900 longitudinal seam according to example 1-   1000 longitudinal seam according to example 2-   1100 longitudinal seam according to comparative example 2

The invention claimed is:
 1. A container precursor, comprising a wall, wherein the wall a) surrounds an interior region and b) comprises a first wall region and a second wall region; wherein the first wall region comprises a first layer sequence, comprising, as overlying layers laid on top of one another from the interior region outwards, a first wall layer, a second wall layer and a third wall layer; wherein, in the first wall region the first wall layer is connected to the second wall layer and the second wall layer is connected to the third wall layer; wherein the first wall layer, as first wall layer sequence from the interior region outwards, comprises a first barrier layer, comprising a barrier plastic for at least 70% by weight relative to the weight of the first barrier layer, and a first carrier layer, comprising one selected from the group consisting of cardboard, paperboard, and paper, or a combination of at least two thereof; wherein the second wall layer, as second wall layer sequence from the interior region outwards, comprises a second carrier layer, comprising one selected from the group consisting of cardboard, paperboard, and paper, or a combination of at least two thereof, and a second barrier layer, comprising the barrier plastic for at least 70% by weight relative to the weight of the second barrier layer; wherein the third wall layer, as third wall layer sequence from the interior region outwards, comprises a third barrier layer, comprising the barrier plastic for at least 70% by weight relative to the weight of the third barrier layer, and a third carrier layer, comprising one selected from the group consisting of cardboard, paperboard, and paper, or a combination of at least two thereof; wherein, in the first wall region, the second carrier layer is characterized by a smaller layer thickness than the first carrier layer, or the third carrier layer, or both; wherein the second wall region comprises a second layer sequence, comprising, as overlying layers from the interior region outwards, the first wall layer, the second wall layer, and the third wall layer; wherein, in the second wall region, the second wall layer is connected to the third wall layer; wherein, in the second wall region, the third carrier layer is characterized by a larger layer thickness than the first carrier layer, or the second carrier layer and the first carrier layer.
 2. The container precursor according to claim 1, wherein the first wall region abuts against the second wall region.
 3. The container precursor according to claim 1, wherein, in the first wall region, the layer thickness of the second carrier layer is 0.05 to 0.9 times the layer thickness of the first carrier layer, or the third carrier layer, or both.
 4. The container precursor according to claim 1, wherein, in the second wall region, the layer thickness of the third carrier layer is 1.1 to 20 times the layer thickness of the first carrier layer, or the second carrier layer, or both.
 5. The container precursor according to claim 1, wherein, in the second wall region, the first wall layer is not connected to the second wall layer.
 6. The container precursor according to claim 1, wherein, in the second wall region a) a surface of the first carrier layer facing the second carrier layer, and b) a surface of the second carrier layer facing the first carrier layer, do not comprise a cover layer and are not connected to a cover layer.
 7. The container precursor according to claim 1, wherein, in the first wall region, a surface of the second carrier layer facing the first carrier layer does not comprise a cover layer and is not connected to a cover layer.
 8. The container precursor according to claim 1, wherein the wall comprises a third wall region; wherein the third wall region comprises a third layer sequence, comprising, as overlying layers from the interior region outwards, the first wall layer and the third wall layer; wherein, in the third wall region, the first wall layer is connected to the third wall layer; wherein the third wall region abuts against the first wall region.
 9. The container precursor, according to claim 1, wherein the barrier plastic has a weight average molecular weight in a range from 3·10₃ to 1·10⁷ g/mol.
 10. The container precursor, according to claim 1, wherein the barrier plastic is one selected from the group consisting of a polyamide, an ethylene/vinyl alcohol copolymer, and a polyvinyl alcohol, or a combination of at least two thereof.
 11. The container precursor according to claim 10, wherein the polyvinyl alcohol is characterized by at least one of the following properties: a) an ethylene content in a range from 20 to 60 mol-%; b) a density in a range from 1.0 to 1.4 g/cm³; c) a melting point of more than 155 to 235° C.; d) an MFR value in a range from 1 to 25 g/10 min; e) an oxygen permeation rate in a range from 0.05 to 3.2 cm³·20 μm/m²·day·atm.
 12. A closed container obtained by folding the container precursor according to claim 1 and closing the folded container precursor with a closing tool.
 13. The closed container according to claim 12, wherein the wall surrounds the interior region on all sides, wherein the wall consists of a one-piece sheet-like composite.
 14. The closed container according to claim 12, wherein one selected from the group consisting of the first layer sequence, the second layer sequence, and the third layer sequence, or a combination of at least two thereof, comprises a further carrier layer.
 15. The closed container according to claim 12, wherein, in the first wall region and the second wall region, the first wall layer is overlaid by a fourth wall layer on a side facing the interior region; wherein the fourth wall layer, as fourth wall layer sequence from the interior region outwards, comprises a fourth carrier layer and a fourth barrier layer, comprising the barrier plastic for at least 70% by weight relative to the weight of the fourth barrier layer; wherein, in the first wall region, the second carrier layer is characterized by a smaller layer thickness than the fourth carrier layer; wherein, in the second wall region, the fourth carrier layer is characterized by a larger layer thickness than the second carrier layer, or the first carrier layer, or both.
 16. The closed container according to claim 15, wherein, further in the third wall region the fourth wall layer overlays the first wall layer on a side facing the interior region.
 17. A process comprising the following process steps a) Provision of the container precursor according to claim 1; b) Folding the container precursor; and c) Closing the container precursor with a closing tool to obtain a closed container.
 18. The process according to claim 17, wherein, prior to process step c), a foodstuff is introduced into the container precursor.
 19. The process according to claim 17, wherein, after process step c), the closed container is autoclaved.
 20. The process according to claim 17, wherein, prior to process step c), the container precursor is sterilized.
 21. A closed container obtainable through the process according to claim
 17. 22. A process, comprising: a) provision of the container precursor according to claim 1; and b) production of a closed container from the container precursor.
 23. The process according to claim 22, further comprising filling the container precursor with a foodstuff.
 24. A process, comprising, as process steps a) Provision of a sheet-like composite, comprising i) A composite layer sequence, comprising A) a composite carrier layer, and B) a composite barrier layer, comprising a barrier plastic for at least 70% by weight relative to the weight of the composite barrier layer, ii) an edge region, and iii) an inner region, abutting against the edge region; b) Reduction of the layer thickness of the composite carrier layer in the edge region; c) Creation of a fold in the edge region to obtain a first edge fold region and a further edge fold region, wherein the first edge fold region and the further edge fold region abut against each other along the fold; d) Bringing the first edge fold region into contact with a first part of the further edge fold region, and connecting a further part of the further edge fold region to the inner region; e) Creation of a further fold in the inner region to obtain a first composite fold region and a further composite fold region, wherein the further composite fold region comprises the edge region; and f) Connecting the first composite fold region to the first part of the further edge fold region and the further part of the further edge fold region.
 25. The process according to claim 24, wherein, in process step e), the further composite fold region comprises a part of the inner region; wherein, in process step f), the first composite fold region is further connected to the part of the inner region.
 26. The process according to claim 24, wherein, in process step b), reduction is carried out by peeling the composite carrier layer.
 27. The process according to claim 26, wherein peeling is carried out by a rotating tool.
 28. The process according to claim 24, wherein, in process step a), the sheet-like composite comprises a crease, wherein in process step e) the creation of the further fold consists in folding along the crease.
 29. A container precursor obtained through the process according to claim
 24. 30. A container precursor, comprising a wall, wherein the wall a) surrounds an interior region and b) comprises a first wall region and a second wall region; wherein the first wall region comprises a first layer sequence, comprising, as overlying layers laid on top of one another from the interior region outwards, a first wall layer, a second wall layer and a third wall layer; wherein, in the first wall region the first wall layer is connected to the second wall layer and the second wall layer is connected to the third wall layer; wherein the first wall layer, as first wall layer sequence from the interior region outwards, comprises a first barrier layer, comprising a barrier plastic for at least 70% by weight relative to the weight of the first barrier layer, and a first carrier layer; wherein the second wall layer, as second wall layer sequence from the interior region outwards, comprises a second carrier layer and a second barrier layer, comprising the barrier plastic for at least 70% by weight relative to the weight of the second barrier layer; wherein the third wall layer, as third wall layer sequence from the interior region outwards, comprises a third barrier layer, comprising the barrier plastic for at least 70% by weight relative to the weight of the third barrier layer, and a third carrier layer; wherein, in the first wall region, the second carrier layer is characterized by a smaller layer thickness than the first carrier layer, or the third carrier layer, or both; wherein the second wall region comprises a second layer sequence, comprising, as overlying layers from the interior region outwards, the first wall layer, the second wall layer, and the third wall layer; wherein, in the second wall region, the second wall layer is connected to the third wall layer; wherein, in the second wall region, the third carrier layer is characterized by a larger layer thickness than the second carrier layer, or the first carrier layer, or both; wherein, in the second wall region, the first wall layer is not connected to the second wall layer. 